The BBC Trust has given provisional approval to the corporation's long-awaited plans for a Freesat service that would offer free digital television by satellite.

The trust, which succeeded the board of governors this year as the BBC's ultimate regulatory body, said the service would "create significant public value" by offering a new way of accessing digital TV services.

BBC managers have drawn up plans for a Freesat service to be run as a joint venture with other public service broadcasters.

Freesat was first proposed in 2003 and then outlined formally by the BBC and ITV in September 2005, when it was envisaged it would launch in the first half of 2006.

The thinking behind Freesat is to give an extra boost to the take-up of digital TV.

The BBC is particularly eager to expand access because of criticism that while all licence fee payers fund its digital services, not all of them can receive them without paying a subscription to satellite or cable.

At the moment Freeview, the digital terrestrial service that does not require subscription, reaches only three-quarters of UK homes, though its penetration will increase as digital transmission signals are strengthened in coming years.

With 7 million households, mainly in rural areas, still analogue-only just a year before the region-by-region switch-off of the analogue signal starts, Freesat is one way of helping to speed up the transition.

The new service would compete with an existing subscription-free satellite service that has been run by BSkyB since October 2004.

"For these homes, the new service would mean being able to access BBC digital services they have already paid for via their licence fee but until now have been unable to receive on a guaranteed subscription-free basis."

She added that Freesat would be in the public interest and encouraged other public service broadcasters to enter into a joint venture with the BBC to get it launched.

ITV welcomed the BBC's announcement that it would go ahead with Freesat.

The commercial broadcaster said it supported the Freesat plan in principle, but was still deciding what an "appropriate level of involvement" would be.

"ITV is supportive of an independent, free-to-air satellite platform which will enable those outside of Freeview coverage areas to receive our family of digital channels," an ITV spokeswoman said.

"We are working closely with the BBC to determine the appropriate level of involvement for us as a business."

Today's Freesat announcement was also welcomed by Help the Aged, with senior policy adviser, David Sinclair, saying it was "now essential that the BBC move quickly and deliver".

"In order to secure a successful switchover to digital, there must be adequate choice for those customers who are not able to afford subscription based services," Mr Sinclair added. "Digital switchover could deliver better television and a whole range of interactive services for older people. Freesat helps fill the gaps and adds to the choice for those unable to get digital terrestrial channels."

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